Search Results (12)

The water environment is a dynamic domain critical to global transportation and commerce, where seaplanes operate during take-offs, landings, and ground operations, often near maritime traffic. Canada’s vast remote regions and unique geography increase reliance on seaplanes, especially for private and recreational purposes. This article examines the intersection of aviation and maritime operations through a mixed-methods approach, analyzing seaplane safety on waterways using quantitative and qualitative methods. First, data from 1005 General Aviation (GA) seaplane accidents in Canada (1990–2022) are analyzed, revealing 179 fatalities, 401 injuries, and 118 destroyed aircraft—significant given that seaplanes comprise under 5% of GA aircraft. Of these, 50.35% occurred while the seaplane was not airborne. Second, insights from interviews, focus groups, and questionnaires involving 136 participants are explored through thematic and content analysis. These capture pilot concerns that are not evident in accident data, such as hazards from jet ski interactions and disruptive boat wakes. The findings highlight risks like limited visibility and maneuverability during waterborne take-offs, worsened by seaplanes’ lack of priority over maritime vessels in shared spaces. This article concludes with recommendations for both the seaplane and maritime communities, including increasing awareness among boaters about the presence and operations of seaplanes, as well as regulatory adjustments, particularly considering the right of way. Full article

A System-of-Systems (SoS) approach is characterized by a strong cooperation between multiple constituent systems to achieve the desired objectives; the performance of an SoS will therefore be dependent on the performance of its constituent systems. However, due to the large number of stakeholders involved in a general SoS scenario, it is not the case that designing and optimizing the constituent systems’ performance with respect to their local design variables will lead to the optimal performance of the given SoS. The aim of the present work is to describe how the design and optimization of two aerial platforms, an all-electric Vertical Take-Off and Landing vehicle and a multi-role hybrid-electric seaplane, will be carried out for a multimodal mobility scenario, accounting not only for the performance-based design requirements but also for needs of all the relevant actors identified in the scope of the proposed use case, illustrating their effects on the architecting of the multidisciplinary design process. This research demonstrates how a structured methodology for the integration of needs and requirements from multiple perspectives can improve the efficiency of the design process, strengthening the connection between the vehicle level and the System-of-Systems level. Full article

To reduce the environmental impact of airborne transportation, the aeronautic community investigates smaller aircraft with short-range operations (such as training aircraft, air taxis, or commuter aircraft) as technology incubators. This paper contributes to this effort by presenting an analysis framework and a detailed case study for integrating an auxiliary solar power system for air taxi operations. The solar power system conceptual design and analysis framework is improved to capture important effects for more realistic analysis for smaller aircraft, such as allowing the solar power system’s efficiency to be estimated as a function of aircraft mission parameters (temperature, speed, cloudiness) and providing a detailed view of the new system’s weight estimation considering potential physical integration scenarios. A detailed analysis of Harbour Air’s seaplane air taxi operations and the DHC-2 Beaver is performed using this enhanced design framework. The results show that the solar power system output exceeds the required secondary electrical power for 86% of the mission in one season; hence, it provides the potential to supplement a hybrid electric propulsion system. Secondly, the authors designed experiments to investigate the sensitivity of technology uncertainties for one critical mission. The results show that a small fuel burn reduction can be achieved with current technologies, with a promising trend of more savings with increasing system efficiency. Also, the results show that accumulated over a season’s operation, the CO₂ emissions from the aircraft can be reduced. The findings indicate that integrating solar power systems can supplement traditional power sources and improve ground operations: specifically, solar energy could power a zero-emission and autonomous air-conditioning system while parked. Overall, integrating solar power into seaplane air taxi operations, even as a retrofit, presents a viable strategy for achieving more sustainable air transportation. Full article

Due to irregular hydrodynamic–aerodynamic coupling, the modeling and simulation of near-surface flight are extremely complex. For the present study, a practical dynamic model and a complete motion simulation method for the solution of such problems were established for engineering applications. A discrete non-linear time-varying dynamics model was employed in order to ensure the universality of the method; thereafter, force models—including gravity, aerodynamic, hydrodynamic, control, and thrust models—were established. It should be noted that a non-linear approach was adopted for the hydrodynamic model, which reflects the influences of waves in real-world situations; in addition, a Proportional–Integral–Derivative (PID) control law was added to realize closed-loop simulation of the motion. Considering a take-off flight as a study case, longitudinal three Degrees of Freedom (DoF) motion was simulated. The velocity, angle of attack, height, and angular velocity were selected as the state vectors in the state–space equations. The results show that, with the equilibrium state as the initial setting for the motion, reasonable time–history curves of the whole take-off phase can be obtained using the proposed approach. Furthermore, it is universally applicable for aircraft operating under hydrodynamic–aerodynamic coupling scenarios, including amphibious aircraft, seaplanes, Wing-in-Ground-Effect (WIGE) aircraft, and Hybrid Aerial–Underwater Vehicles (HAUVs). Full article

Seaplane operations connect remote areas, promote tourism, and provide unique transportation solutions. After many years of preparations, commercial seaplane operations on a network of 100 water airports and 200 waterways in Greece are about to commence. The network can serve the needs of 1.6 million permanent residents of the Greek islands, the inhabitants of the mainland, and over 35 million annual tourists. This paper aims to conduct a PESTLE (Political, Economic, Social, Technological, Legal, and Environmental) analysis to identify the factors that have delayed operations and those that will affect the success of future operations. As such, 26 factors are examined. It was found that the Greek debt crisis and the COVID-19 pandemic were impediments to operations. The potential of using electric seaplanes is discussed. Recent developments in using drone inspection capabilities for aviation safety are examined. Management strategies for the Etesian winds and other environmental issues are presented. Overall, seaplane operations have enormous potential, while the Greek economic recovery provides favorable conditions for completing the project. The critical issue determining success is executing a multi-faceted business model to ensure seaplane operations’ financial viability. The network can act in synergy with other modes of transportation to help achieve social cohesion, improve tourism services, and foster economic development. Full article

To reduce the aerodynamic performance degradation caused by the sculling phenomenon on the flap of amphibious seaplanes, this study proposes a grid-slat fusion design method that integrates grid channels into the slats to create multiple lift surfaces. This new configuration enhances not only the lift capacity of the slats but also the lift characteristics of the main wing, leveraging ejector effects from the grid channels. A grid-slat fusion configuration parametrization method is developed based on the “new conic curve” concept, and an optimization approach is implemented using the NSGA-II algorithm. Computational fluid dynamics (CFD) verification of the 30P30N airfoil demonstrates that the grid-slat fusion design enhances the lift-to-drag ratio of the optimized 2D configuration by up to 8.5% at a specific condition, thereby significantly improving its aerodynamic performance at high angles of attack and meeting the requirements for take-off and landing. The three-dimensional configuration demonstrates a stall angle of attack delay of 2° and a maximum lift coefficient increase of 6%. Furthermore, the grid-slat composite configuration allows a better lift-to-drag ratio, and its aerodynamic characteristics improve with increasing wave height. During the wave runup phase, aerodynamic performance is further enhanced, with different wave positions significantly influencing the aerodynamic performance. Full article

The electric seaplane, designed for take-off and landing directly on water, incorporates additional structures such as floats to meet operational requirements. Consequently, during the take-off taxiing phase, it encounters significantly higher aerodynamic and hydrodynamic resistance than other aircraft. This increases energy demand for the electric seaplane during the take-off phase. A mathematical model for energy consumption during this stage was developed by analyzing resistance, using the propeller pitch angle as an optimization variable. This study proposes a coupled energy efficiency optimization method for the take-off phase of an electric seaplane’s electric propulsion unit (EPU). The method aims to determine an optimal propeller pitch angle configuration aligned with the seaplane’s design criteria. This ensures that the propeller output thrust meets minimal requirements during take-off while enhancing energy efficiency. Experimental validation with the two-seater electric seaplane prototype RX1E-S has demonstrated that selecting the optimal propeller pitch angle can effectively reduce energy consumption by approximately 10.4%, thereby significantly enhancing flight efficiency. Full article

In this paper, the ditching performance of a seaplane model on calm water and a uniform water current coupled with wind was numerically investigated. The overset grid technique was applied to treat the large amplitude of the body motions of the seaplane without leading to mesh distortion. The effects of the initial velocity and the initial pitch angle on the slamming loads and motion responses were investigated for the seaplane’s ditching on calm water. A good agreement with the experimental data on the velocity and angle was obtained. Besides ditching on calm water without the water current and wind, three more-complicated conditions were adopted, including the seaplane’s ditching on calm water with wind, a water current without wind, and a water current coupled with wind. The accelerations and impact pressures of the seaplane can be influenced by the wind or current. Water splashing and overwashing could be observed during the water entry process, with water overtopping the seaplane head or nose and flowing over the body surface. It can be concluded that the relative motion between the water and the seaplane model should be carefully controlled to avoid possible damages caused by the occurrence of overwashing. Full article

This paper introduces the conceptual design of a submersible seaplane that merges the maturity of the wing-in-ground (WIG or ekranoplan) crafts and seaplanes with covert hybrid underwater insertion, travel, and recovery. WIG crafts have a higher lift-to-drag ratio and thus improved endurance, while hybrid crafts have recently become feasible due to advances in materials, electric propulsion, and multi-medium computational fluid dynamics. The reconnaissance design can insert, loiter, and extract from underwater, surfaces if necessary; it can fly in or out of ground effect, keep watch on the sea surface while recharging, and travel underwater. This design minimizes Doppler and infrared signatures to evade the surface wave, backscatter radar systems, and cube satellite arrays typical in contested maritime areas. Five critical enabling technologies are overviewed, showing how they enable a conceptual design. This project was conducted in collaboration with two industrial partners, namely Ron Allum and Thales Australia. The conceptual design has been socialised and confirmed at technical conferences from each core discipline and partly confirmed by a recent Chinese design and testing of a similar hybrid uncrewed aerial vehicle (HUAV). Recommendations are made for improving the conceptual design before proof-of-concept prototype testing. Given the seminal nature of HUAV design and research and some of the unique innovations proposed, the lessons learned from this iteration will likely be significant to other designers and researchers. Full article

Design optimization on the Indonesia N219 seaplane catamaran is necessary to provide better service to rural islands of Indonesia. This research aims at decreasing drag using a design based on biomimicry by imitating the hydrodynamic characteristics of sailfish (Istiophorus platypterus) for pontoon floats. The design is then validated using a numerical fluid test using ANSYS Fluent to see the reduction in drag due to the change from a conventional or Wipeline^® 13000 design to a biomimetics adaptation design. Next, further optimization was carried out based on the adaptation design based on trim tests, clearance tests, and deadrise angle dimensions suitable for biomimicry designs at Froude number speeds of 0.4 to 0.7. The design results with the adaptation of biomimicry show that a change in the design with this optimization affects a drag reduction that reaches 30% of the total drag generated by the conventional design. Full article

Nowadays, with the escalating tensions in maritime dispute and the development of marine economy, there has been renewed interest in seaplanes for their special capacity of taking off and landing on water. Prediction of take-off performance, involving aerodynamic analysis and hydrodynamic analysis, is a main challenge in seaplane design, while the prediction methods have been little improved since the 1960s. This paper aims to investigate the attitude and resistance characteristics of a seaplane at different speeds during the take-off by numerically modeling the air-water flow field using RANS equations with VOF method. The trim and heave motion of seaplane in response to aerodynamic forces, hydrodynamic forces, hydrostatic forces, and propeller thrust was realized by solving rigid body dynamics equations and adopting dynamic overset mesh technique. The variations in heave, trim angle, and resistance characteristics during the takeoff were investigated, and their inherent relationships with the aerodynamic, hydrodynamic, and hydrostatic performance were revealed. Particular investigation on the hydrodynamic resistance indicates that the stagnation line located at the convex bow would contribute a considerable increase of pressure resistance at the first hump, and the trim angel of a seaplane should be operated in an optimum trim range, typical between 4–6 deg, to minimize the hydrodynamic resistance at the second hump. Additionally, the dynamic motion convergence study proves that the utilization of damping terms was an effective way to accelerate the convergence of the dynamic motion ending with a quasi-static state. Full article

Seaplanes have become popular tourism and transportation tools with the ability of take-off and land on water. Recent seaplane accidents are highlighting the need for safety analysis of the seaplane operation process, which includes the sequential stages of water-taxiing, take-off, flight, and landing. This paper proposes a novel approach to modeling the risk of seaplane operation safety using a Bayesian network (BN). The rough risk factors that may cause seaplane accidents are identified by historical data, literature review, and interviews with experts. Based on the identification result, a risk evaluation indicator system is constructed and screened by the Delphi method. The structure of the proposed BN is derived from the indicator system. The parameter of the BN is obtained by expert experience and parameter learning from statistical data. The BN model is validated with an out-of-sample test demonstrating nearly 95% prediction accuracy of the accident severity level. The model is then applied to conduct diagnosis inference and sensitivity analysis to identify the key risk factors for seaplane operation accidents. The result shows that the four most critical risk factors are mental barrier, mechanical failure, visibility, and improper emergency disposal. It provides an early warning to take appropriate preventive and mitigative measures to enhance the overall safety of the seaplane operation process. Full article